He didn't mention it, but indirect good was taken into account by Armok's argument because of its wideness. If what you value most is life, more than anything ever, then, be it directly or indirectly, you do everything you can to save lives. If you don't, then what you value most isn't life. This was the first statement, and it couldn't be simpler.
I will repeat that no, there isn't any difference, morally speaking. Let's say that in one room there is a man and a button : if he pushes the button then someone dies. In another room there is another man and another button : if he doesn't push the button then someone dies. If they both kill someone, one of them isn't less guilty than the other. It isn't about appearances of action or inaction, it's about the choices you make : if all that matters is the number of lives at the end, then whether you fired the gun or not isn't important.
Now, thinking it implies that you are guilty of killing everyone you didn't save is wrong. You actually are guilty of preferring to do something other than saving lives every time you aren't trying to save lives, though, this is an undeniable fact. Whether you are more or less okay with it is another matter.
The example sounds ridiculous because you voluntarily neglected the "life is sacred" part. Let's quit thinking up metaphors and see the core of the problem : someone pretends to value something that much while his actions prove that he doesn't. Some people don't like that. All that was said was : it would be better if you had the wisdom to know what your values are and the courage to act according to them.
If you still don't agree then we're going in circles.